Rocky
Acres
Cave
While finishing off the exploration of
However above the rising at Rydon (to which the Lindridge water drains) is the disused Rydon Quarry which breached a large cave passage over thirty years ago. The cave was reputed to contain rifts descending to water level but accounts are sketchy and what remains of the cave lies under 40 feet of overburden dumped during the construction of the nearby by-pass. A number of small cavities above the old quarry were revealed by top soil stripping and blasting for the by-pass and the land owner John Jones who became fascinated by the story of the original cave has spent six years digging in them.
Assisted by members of the PCG and DSS he concentrated mainly on one cave now dubbed Rocky Acres which by the time we first visited the site last summer had reached a depth of 15 metres and a length of 30 metres. This was achieved by using a compressor powered rock drill and rock splitting wedges to enlarge the narrow phreatic rift. What has lured diggers is the draught which the cave possesses plus the fact that although narrow it is still going. On cold frosty mornings steam billows from the entrance.
Our contribution was to entice an assortment of individuals into blasting through a particularly hard band of limestone at the head of a narrow rift. Prior to our first visit the cave ended in a wriggle into an excavated pot off which led the rift. It had been originally approached from an alternative direction by Geoff Chudley and Co. but they had backfilled this to get a more direct route to the bottom. The dig had begun to look so daunting that at that point they had gone elsewhere. Altogether about 15 visits have been made to the site since last June and the cave has been blasted 8 separate times by members of DSS, BEC and WCC. Rock and spoil removal has been mainly by Pete Rose and myself and members of the Rock House team.
Back filling has been accomplished by using stemples, drystone walling and stabilisation with liquid cement. As we go deeper removal of spoil for a pair of diggers gets more tricky although there is plenty of room to stack boulders.
By the time we had squeezed into the wider part of the rift the floor was covered in a layer of rubble which was added to by successive bangs, slumping in of back filled material and digging in the wrong place by persons unknown!
However as the spoil and fractured rock was removed tantalising holes in the floor began to appear and the slight draught increased. The floor now consists of soft mud and water worn boulders which can be removed without blasting and the rift bells out to a width of 3 feet at floor level.
Digging conditions are a lot more pleasant than Skullcap and the site is far more promising. As we go down it seems to me that the entrance passage is feeding into something much larger and partially choked. This would seem to support the hypothesis that large phreatic passages should exist near resurgence level. We are an estimated 20 to 30 feet above the rising, at the bottom of the cave, which puts us very near the estimated level of the original Rydon cave - we are also virtually at or below the original quarry floor level. With a depth potential of 85 metres and 2 km. straight line distance to the furthest feeder sink there ought to be a significant cave underneath us!
Diggers are welcome and tools are on site. However do not be tempted to climb over the
gate from the bypass - cars can be driven to the entrance and John Jones is
pleased to welcome bona fide cavers. To
find Rocky Acres drive up
Perhaps we'll see you down there sometime. Pete and I normally go on Wednesdays.
Peter Glanvill February 1991